Association of MS4A6A, CD33, and TREM2 gene polymorphisms with the late-onset Alzheimer’s disease

Alzheimer’s disease (AD), which is a progressive neurodegenerative disorder, causes structural and functional brain disruption. MS4A6A, TREM2, and CD33 gene polymorphisms loci have been found to be associated with the pathobiology of late-onset AD (LOAD). In the present study, we tested the hypothesis of association of LOAD with rs983392, rs75932628, and rs3865444 polymorphisms in MS4A6A, TREM2, CD33 genes, respectively.

In the present study, 113 LOAD patients and 100 healthy unrelated age- and gendermatched controls were selected. DNA was extracted from blood samples by the salting-out method and the genotyping was performed by RFLP-PCR. Electrophoresis was carried out on agarose gel. Sequencing was thereafter utilized for the confirmation of the results.

Only CD33 rs3865444 polymorphism revealed a significant difference in the genotypic frequencies of GG (P=0.001) and GT (P=0.001), and allelic frequencies of G (P=0.033) and T (P=0.03) between LOAD patients and controls.

The evidence from the present study suggests that T allele of CD33 rs3865444 polymorphism is associated with LOAD in the studied Iranian population.